1. Field of the Invention
The present invention relates to a light emitting diode operating and examination light system and more particularly pertains to illuminating an area for performance of a medical operating procedure and medical examination with minimum heat generated and energy required in association with maximum efficiency.
2. Description of the Prior Art
The use of operating and examination light systems of known designs and configurations is known in the prior art. More specifically, operating and examination light systems of known designs and configurations previously devised and utilized for the purpose of illuminating an area on a subject for performance of a medical operating procedure and medical examination are known to consist basically of familiar, expected, and obvious structural configurations, notwithstanding the myriad of designs encompassed by the crowded prior art which has been developed for the fulfillment of countless objectives and requirements.
By Way of Example, U.S. Pat. No. 4,316,237 to Yamada et al., Feb. 16, 1982, discloses a Lighting Fixture for Use in Medical Operations and Therapeutic Treatment. U.S. Pat. No. 4,380,794 to Lawson, Apr. 19, 1983, discloses a Surgical Lamp Characterized by Having an Improved Reflector. U.S. Pat. No. 4,608,622 to Gonser, Aug. 26, 1986, discloses a Multi-function Light Source. U.S. Pat. No. 4,630,182 to Moroi et al., Dec. 16, 1986, discloses an Illuminating System. U.S. Pat. No. 4,651,257 to Gehly, Mar. 17, 1987, discloses a Multiple Source Lighting Fixture. U.S. Pat. No. 4,288,844 to Fisher et Al., Sep. 8, 1981, discloses an Electrically Focused Surgical Light. U.S. Pat. No. 5,093,769 to Luntsford, Mar. 3, 1992, discloses a Surgical Lighting System. U.S. Pat. No. 5,274,535 to Gonser, Dec. 28, 1993, Discloses a Dental Operating Light with Color Correction. U.S. Pat. No. 5,580,163 to Johnson Ii, Dec. 3, 1996, discloses a Focusing Light Source with Flexible Mount for Multiple Light-emitting Elements. U.S. Pat. No. 4,254,454 to Hardin, Jr., Mar. 3, 1981, discloses a Self-ventilating Dental Lighting Device. U.S. Pat. No. 4,118,761 to Dey, Oct. 3, 1978, discloses a Light Condensing Illuminator. U.S. Pat. No. 3,704,928 to Coombs et Al., Dec. 5, 1972, discloses a Dental Light with Dichroic and Infrared Filters. U.S. Pat. No. 3,702,928 to Alger, Nov. 14, 1972, discloses an Adjustable Lighting Apparatus. U.S. Pat. No. 2,846,566 to F. Gunther et al., Aug. 5, 1958, discloses an Operating Table Lamp. U.S. Pat. No. 2,280,402 to E. H. Greppin, Apr. 21, 1942, discloses a Dental Operating Lamp. U.S. Pat. No. 2,088,024 to E. Baber, Jul. 27, 1937, discloses an Operating Room Lamp. U.S. Pat. No. 2,069,950 to E. H. Greppin, Feb. 9, 1937, discloses a Surgical Lamp.
A series of recent patents granted to Color Kinetics Inc., 10 Milk St. Suite 1100, Boston Mass. 02108 treats the combined use of microprocessor controlled colored LEDs to produce wide spectrum light including color corrected white light.
While these devices fulfill their respective, particular objectives and requirements, the aforementioned patents do not describe a light emitting diode operating and examination light system that allows illuminating an area for performance of a medical operating procedure and medical examination with minimum heat generated and energy required in association with maximum efficiency.
It is desirable to replace current medical operating and examination lights with versions employing light emitting diodes (LEDs) for the useful purposes of reducing electrical power consumption, extending lamp lifetime, and mitigating problems with heat generation in present fixtures. In addition, lighting systems employed in operating rooms where oxygen and various combustible gases, such as cyclopropane, may be used, should not incur an explosion hazard as is possible from exposed surface temperatures in excess of about 200 centigrade or in the event of an electrical spark as in igniting a high intensity discharge lamp. Current medical operating and examination lights susceptible to replacement by an LED version are widespread throughout the industry. These lights are currently available in units producing either a well defined pattern of illumination as in a dental version typically having a 24 inch projection distance forming a fixed rectangular illuminated area with little or no stray light hereinafter referred to as the high definition version, or a version illuminating a wider area of a patient over larger distances with lesser concern for stray light hereinafter referred to as a low definition version.
The prior art illumination light source for the high definition light is generally a single extended filament halogen lamp operating at about 150 watts. Light from the source is collected by a large shallow parabolic trough main reflector thereby generating a roughly rectangular illumination zone over a large range extending through the desirable 24-inch nominal working distance. Light emanating from the lamp not reaching the reflector is either blocked or is directed back through the parabola's focal line to be reflected by the main reflector toward the patient. Much of the input electrical power is converted into heat and must be dissipated using a heat transmitting glass reflector or other heat dissipation means. The high definition light is not a fixed light and is generally affixed to an articulated arm thereby permitting the medical practitioner to manually adjust the illuminated area of the patient. The high temperature of external parts associated with heat dissipation often creates an undesirable response should the practitioner inadvertently touch the main reflector or other hot parts of the light housing.
The prior art for the low definition light varies, but most frequently comprises a series of standard reflectorized halogen lamps, each known in the industry as an MR-16 operating at up to 75 watts power consumption. Higher output powers are available, however lifetime is reduced dramatically for lamps over 75 watts. A typical light employs four or more halogen MR-16 lamps. One arrangement comprises four MR-16 lamps affixed to a pair of substantially rectangular members crossing and joined at their centers. The MR-16 lamp can exhibit as much as 4,000 hours lifetime under ideally ventilated conditions, but it is generally known that in practical applications in a partial enclosure, particularly when the lamp is repositioned occasionally and cycled on and off repeatedly, the actual lifetime experienced is substantially less than 4,000 hours.
Significant savings in electrical power consumption and operating cost can be realized by providing LED based high definition and low definition lights for medical operating and examination purposes. It is the intent of this disclosure to describe techniques to introduce LEDs into the general operating and examination light art whereby less heat is generated and lamp lifetime is extended to enable operation for a minimum five-year period without lamp replacement. The principles and elements of this disclosure are not limited to a medical operating or examination lighting system, rather the concepts presented herein are extendible to broader classes of lights in even more general lighting applications.
Selected embodiments of the high and low definition operating and examination lights are outlined in the following. The number of LED sources needed to achieve usable illumination is a function of the state-of-the-art in LED technology. Generally the number of LEDs will not exceed thirty emitters at present. The use of LEDs emitting two or more different colors may be employed to provide color correction as well as color temperature changes more suitable for specific medical operating or examination applications.
In this respect, the light emitting diode operating and examination light system according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in doing so provides an apparatus primarily developed for the purpose of illuminating an area for performance of a medical operating procedure and medical examination with minimum heat generated and energy required in association with maximum efficiency.
Therefore, it can be appreciated that there exists a continuing need for a new and improved light emitting diode operating and examination light system which can be used for illuminating an area for performance of a medical operating procedure and medical examination with minimum heat generated and energy required in association with maximum efficiency. In this regard, the present invention substantially fulfills this need.